fix: openapi for eval-task (#1085)

# What does this PR do?
- as title

## Test Plan
- the deprecated endpoint need to obey what it was before

[//]: # (## Documentation)

docs/_static/llama-stack-spec.yaml

@@ -35,7 +35,7 @@ paths:
               $ref: '#/components/schemas/DeprecatedEvaluateRowsRequest'
         required: true
       deprecated: true
-  /v1/eval-tasks/{task_id}:
+  /v1/eval-tasks/{eval_task_id}:
     get:
       responses:
         '200':
@@ -51,7 +51,7 @@ paths:
       description: ''
       parameters:
         - name: eval_task_id
-          in: query
+          in: path
           required: true
           schema:
             type: string